He wants you to send a text message to a SMS billing service, where they will charge X amount to your phone bill. Then, the billing service will send Wernis less than what you paid, and in return, Wernis will pay you about 10% of what it cost.
For example:
You send a text message to the SMS billing service and they charge you $20.
SMS billing service will send Wernis $15
Wernis will send you $5, yielding him a $10 profit.
Although this may seem stupid for you to do, some people actually have extra money racked up on their phone and have nothing to do with it.